Sour Face enjoys denigrating Charanko for his lack of etiquette in practicing martial arts, from slacking off during training to entering the Super Fight tournament behind Bang's back, although in the latter case he was unaware that Saitama had entered under the then-injured Charanko's name. As one of Bang's former disciples, Sour Face holds his former master in high esteem.[2] He also nurses a grudge against Garou, who had rampaged across the dojo and severely injured him, forcing him to quit. However, he still fears Garou: Saitama emphasizes that Sour Face had left Bang's dojo after the incident and entered the Super Fight to "pretend to fight" Garou, whereas Charanko had challenged Garou alone and head on, albeit foolishly.

Sour Face is also very nervous in front of crowds.[3] After his fight with equally nervous Giga Pro-Wrestling fighter Jakumen, Sour Face, who feared being embarrassed with defeat by his opponent, praises him abundantly after his victory. In part due to this nervousness, he becomes friendly with and strikes up an informal alliance with "Charanko" to survive the tournament, helping him fix the disguised Saitama's belt, and praising him for insulting Zakos after Zakos insulted both him and Bang. Upon realizing that "Charanko" was about to fight the horribly violent Bakuzan, Sour Face strongly cautions him about the lethality of his opponent's attacks.
Sour Face is also a trusting individual as he still believes Saitama to be Charanko after his wig is knocked off.

Sour Face is participating in the Super Fight Tournament. He has a short discussion with Saitama (who is disguised as Charanko) about an incident that happened at the martial arts tournament in the past, when Garou decided to enter the tournament disguised as Wolfman, indirectly causing Saitama to become nervous by noting that the police will be called in if disguises are used during the tournament. He also states that he wishes to win the tournament so that he will never be intimidated if he ever faces Bang or Garou in the future and reminisces Garou's rampage through the dojo. Saitama outright states that what Sour Face is doing is pitiful, as he is simply using the tournament to pretend to fight Garou while Charanko had fought Garou head on by himself. Sour Face leaves the waiting room aggravated, directing a challenge at Saitama so that they might both fight in the ring.[4]

After the tournament introductions, Saitama converses with Sour Face when Zakos appears and starts questioning Saitama. Sour Face ends up answering some of Zakos questions. Zakos then reveals that Bang was supposed to be one of the judges, much to Sour Face's surprise, and starts mocking the martial arts master. Sour Face starts to feel very insulted, but felt even angrier when "Charanko" did not seem angry at Zakos's comments. Saitama replies that he was not invested in the conversation and is only looking forward to fighting Zakos, but notes that Zakos doesn't seem strong. Sour Face compliments Saitama's remarks.[5] Later, Sour Face explains to Saitama what a reverse seed is and shows him the tournament list, stating "Charanko" is a reverse seed to.[6]

While watching the match between Max and Suiryu, he was shocked by the latters strength, easily defeating his opponent.[7] Later Sour Face was pitted against Jakumen in his first match with both men being visibly nervous.[8] He defeats Jakumen and both exchange praise after the match, with the commentators praising the sportsmanship between the two.[9] During the match between Saitama and Bakuzan, he watches the match with a nervous outlook since he expects a brutal blood bath. However, after Saitama upper-cuts Bakuzan into the air, he is deeply shocked at Saitama's power and the easy defeat of Bakuzan.[10]

During his match against Saitama, he proclaims that Saitama's victory against Bakuzan was sheer luck and promises to show him the true meaning of martial art powers. Ironically enough, he is ultimately defeated with the same uppercut and in the same manner as Bakuzan.[11]

In the match against Choze, he once again warns Saitama about Choze's brutality in his turn in the semi-final. However, once again he is met with disbelief when Saitama sends Choze flying in two seconds. As a result, he begins to lament the fact that Saitama is going to be champion.[12] During the match between Saitama and Suiryu, he wondered what they were talking about and assumed it was about their harsh path to the finals.[13] During the match, Sour Face worried for Saitama injury. He was amazed that Saitama could keep up with Suiryu, until Sneck and Max showed up and point out Suiryu fighting style.[14] After Saitama's wig was blown off, Sour Face was still convinced it was Charanko and was believed Charanko had problem with baldness.[15]

Sour Face was later present at the closing ceremony, when it was suddenly interrupted by The Three Crows and Gouketsu, who tells them they will become monsters.[16] Sour Face and the other martial artist were given a choice to become a monster or die, visibly frightened he was shocked to see some of the fighter accepting the offer.[17] He later watched Suiryu fight the transformed martial artist's and was saved from Choze's energy ball attack.[18] When Suiryu considered to become a monster, Sour Face frighteningly watched, but was relieved that it was never his intention and cheered for Suiryu.[19] Sour Face was then knocked out by the crows, along with the rest of the martial artist.[20]

Sour Face cites himself as the second most powerful disciple after Garou, who implicitly confirmed his skill by approaching him to voice his intent to rampage in the dojo. Furthermore, although Bang had claimed that all his best disciples beaten by Garou were crippled for life, Sour Face, who was among those disciples who suffered injury at Garou's hands, does not seem to be debilitated by his past injuries.

As he had used Charanko as a training dummy for his strangulation moves in the past, Sour Face is likely capable of executing them as well.